X-ray shutter apparatus with rotary mounting means and specific means for rotating the shutter apparatus thereon



Nov. 22, 1966 w, R. I L s 3,287,561

X-RAY SHUTTER APPARATUS WITH ROTARY MOUNTING MEANS AND SPECIFIC MEANS FOR ROTATING THE SHUTTER APPARATUS THEREON Filed June 11, 1964 United States Patent 3,287,561 X-RAY SHUTTER APPARATUS WITH ROTARY MOUNTING MEANS AND SPECIFIC MEANS FOR ROTATING THE SHUTTER APPARATUS THEREON William R. Ingles, Houston, Tex., assiguor to Westinghouse Electric Corporation, Pittsburgh, Pa., 2 corporation of Pennsylvania Filed June 11, 1964, Ser. No. 374,400 2Claims. (Cl. 250-105) The present invention relates to X-ray apparatus, and more particularly to X-ray shutter apparatus.

It is the practice to provide on X-ray screen frames and on spot film devices a shutter mechanism which is adjustable bi-directionally to control mutually-transverse dimensions of an X-ray beam-defining aperture. It is the practice to confine the beam in two directions, and for this purpose two pairs of shutters are provided, each pair being controllable separately from the other to define a variable beam aperture of rectangular cross section. This shutter mechanism is interposed between the patient and the X-ray source and acts to define the size and crosssectional shape of the beam which passes through the patient. Its adjustment is so selected as to embrace the internal area of the patient to be observed, and it is desirable in behalf of enhancing clarity of the screen picturization and minimizing the exposure of the patient that such area be minimized, commensurate with inclusion of the desired picturization.

In view of the foregoing remarks, it becomes a prime object of the present invention to an X-ray shutter apparatus which is adjustable to define a narrow aperture which may be aligned with an elongated, narrow, patient exposure area for picturization of such as veins and arteries extending in various directions, without requiring movement of the patient to obtain such alignment.

Such object is obtained in the present invention by providing, in general, a bi-directionally adjustable shutter means which is capable of rotary movement about the center of the X-ray aperture which it defines, to thereby enable such aperture to be aligned in accord with direction of extension of a narrow internal portion of the patient to be observed.

Other objects, features, and advantages of the invention will become apparent from the following detailed description, taken in connection with the accompanying drawings, in which:

FIGURE 1 is a schematic representation in plan view of an illustrative embodiment of the invention; and

FIG. 2 is a front elevation view, partly in outline and partly in section, taken in the direction of the arrow 2 in FIG. 1.

Referring to FIGS. 1 and 2, the illustrative shutter mechanism 4 is disposed within an X-ray table 5, only a fragmental portion of which is shown in FIG. 2, beneath the patient-supporting surface or top 6 of such table, and is arranged for longitudinal and transverse movement therealong in coincidence with an X-ray tube means 7 by way of a longitudinal carriage 8 and a cross carriage 9. Cross carriage 9 directly supports X-ray tube means 7 via a flanged union 10 and is movable on carriage 8 via supporting rollers 11. Longitudinal carriage 8 carries the cross carriage 9 and is movable longitudinally along the table via rollers 12 on tracks 13 within the table (only one track being shown).

The X-ray tube means 7 is oriented in a conventional way to direct an X-ray beam upwardly, along an axis 16, through the shutter mechanism 4 and perpendicularly through the table top 6. The carriage 9 includes a hollow cylindrical portion 17 which acts to shield the X-ray beam enroute to the shutter mechanism 4. The shutter mecha- "ice nism 4, in a well-known manner, serves to define the size and shape of the X-ray beam which passes upwardly through the table top and patient thereon to the usual X- ray film, fluorescent screen, or other X-ray-sensitive picturization means (not shown).

The shutter mechanism 4 comprises two pairs of horizontally-disposed shutters, a first pair of shutters 20a and 20b, and a second pair of shutters 21a and 21b. These shutters are made of lead, or other X-ray opaque material, and are in fiat-sheet form of suitable thickness to substantially block the passage of X-rays except for the central clearance therebetween which defines the aperture 23 for the X-ray beam projecting along the axis 16.

Each shutter 20a, 20b, 21a and 21b, includes a rectangular plate portion 24 and an elongated arm portion 25 extending therefrom at one edge. The shutters of each pair are arranged in the same plane, with the plate portions oppositely arranged to define a pair of parallel side edges of the aperture 23, and with the arm portions 26 extending in opposite directions on opposite sides of the plate portions.

To support and adjust the proximate positions of the shutters, shutters 20a and 20b are pivotally connected to and supported by flat segmental-disc-shaped members 28 and 29 which are rotatably mounted on posts 26' and 27, respectively. The shutter 20a is pivotally connected at one extreme edge of its plate portion 24 to one edge of the member 28 by a pivotal securing means 30a, and is pivotally connected at the end of its arm portion 26 to a corresponding edge of the member 29 by a pivotal securing means 31a. Member 28 is turned by a reversible slow-speed electric motor mechanism 32, such as a reversible gear-reducer clock-motor, via a shaft 33 and drive pulley 34 that frictionally engages the circular rim portion of segmental disc-shaped member 28. Turning of the member 28 in one direction moves the shutter 20a in a direction to expand the respective edge of the aperture 23, and turning of the member 28 moves the shutter 20a oppositely. During such movement, the member 29 is moved correspondingly with member 28 via shutter arm 26 and pin means 31 and such member aids in supporting and directing movement of the shutter. The other shutter 20b is moved simultaneously by turning movement of member 28 by Way of a corresponding pin means 3012. By virtue of the linkage arrangement the two shutters 20a and 20b move inwardly in unison to contract the one dimension of aperture 23 and outwardly in unison to expand such dimension, according to direction of turning of member 28 about the post 26', as determined by operation of motor mechanism 32.

The shutters 21a and 21b are similarly arranged in a plane beneath shutter pair 20a, 20b and are in extension transversely thereof. Operation of shutters 21a and 21b is similar to but independent of that of shutters 20a and 20b, but the dimension of aperture 23 controlled thereby is transverse to the dimension controlled by shutters 20a and 20b. Description of operation of shutters 20a and 20b applies also to shutters 21a and 21b, and the corresponding parts are given the same reference characters as prime numbers.

In FIG. 2 of the drawings, the shutter plates are shown for clarity as vertically spaced away from the segmental disc members 28, 28 and 29, 29' which support them. In actual practice, the shutter plates slidably rest on these members to give widthwise support without need for other than simple, non-supporting, pin connections at 30a, 30b, 31a, 31b, 30a, 30b, 31a and 31b.

In accord with a prime feature of the invention, both pairs of shutter mechanisms are mounted on a rotary support member 40 which is constructed and arranged for rotary movement about the axis 16 of the X-ray beam Q) to enable the rectangular shape thereof as defined by shutter aperture 23 to be selectively aligned as desired with the parts of the patient undergoing observation.

Rotary support member 40, as illustrated herein, is in the form of a thin annular member in coaxial alignment with axis 16 and disposed beneath and parallel to the shutters. Its central evacuated portion (not shown) permits of unobstructed passage of the X-ray beam to the shutters. The upper surface of member 40 supports the posts 26 and 27 which support the members 28, 28', 29 and 29', which in turn support the shutter pairs 20a, 20b and 21a, 21b. The underside of member 40 serves as support for the motor mechanisms 32 and 32' which drive the members 28 and 28' for shutter adjustment. Attachment of these components to the support member 40 is by any suitable means such as machine screws (not shown).

To obtain rotary movement of the member 40, and thereby the aperture 23, such member 40 is rotatably supported at its outer edge by a plurality of circumferentially-spaced-apart double-flanged rotatable support and guide wheels 42 which are mounted on pedestals 43 secured at their bases to a flanged portion 44 of the cross carriage 9. To turn the member 40 selective degrees in either rotary direction, a slow-speed electric motor mechanism 45, similar to motor mechanisms 32 and 32', is employed which is mounted on the underside of such member 40 and includes an output shaft 46 which extends upwardly through such member. Motor mechanisms 45 is drivingly connected to member 40 for turning same through the medium of a pulley 47 secured to the shaft 46 and a flexible cable 48 encircling the pulley and anchored at opopsite ends to vertical anchor posts 49 and 50, respectively, which are carried by and extend upwardly from the flanged portion 44 of the cross carriage 9. A

helical tension spring 51 in series with cable 48 assures a tight friction-gripping relationship between such cable and the pulley 47 to assure that the latter will travel along the former to cause rotary movement of member 40 when the motor mechanism 45 is operated.

From the foregoing description it will be apparent that the pairs of shutters 20a, 20b and 21a, 21b may be adjusted remotely by controlling the operation of the reversible motor mechanisms 32 and 32' to obtain such as a narrow slit-like shape for the X-ray-beam-defining aperture 2.3, a shape which is commensurate with the width of a patients artery or vein, for example, and by selective rotation of the support member 40 for these shutter pairs, such aperture may be brought into registry and alignment with such vein or artery.

In addition to such alignment-affording feature of the invention, it will be apparent that the remotely-controlled shutter mechanisms per se appear to offer structural advantages over previously used mechanisms.

While the invention has been described in connection with an exemplified construction, various modifications thereof will become obvious to those skilled in the art. It is not desired, therefore, that the invention necessarily be limited to the specific arrangements shown and described, and it is intended to cover in the appended claims all such modifications as fall within the true spirit and scope of the invention.

I claim as my invention:

1. X-ray apparatus comprising shutter means defining an elongated aperture which dictates the cross-sectional shape of an X-ray beam, and rotary mounting means for said shutter means to permit selective rotarywise orientation of said shutter means, wherein said rotary mounting means is in the form of a circular member and said apparatus includes roller support means engaging the outer rim of said member for rotatable support thereof, a motor mechanism mounted on said member, a pulley mounted on said mechanism and rotated by same, and a tensioned flexible cable means anchored at both ends at spaced points on said apparatus and passing around said pulley to cause said pulley to travel along said cable means during pulley rotation and cause said motor mechanism and thereby said mounting means to turn on an axis prescribed by said roller support means.

2. X-ray apparatus comprising an X-ray table having a table top for support of a patient, an X-ray tube means mounted on said table beneath said table top and constructed and arranged for directing an X-ray beam upwardly through said table top, a rotary support member mounted on said table in interposition between said X- ray tube means and said table top, said support member having a circular outer rim, roller means mounted on said table for engagement with such circular outer rim for support of said support member in coaxial alignment with an axis of symmetry of said X-ray beam, a motormechanism mounted on said rotary support member and including a pulley driven thereby, flexible cable means, anchor members mounted at spaced points on said table, securing opposite ends of said cable means and passing around said pulley for travel therealong during operation of said motor mechanism to turn said rotary support member, and two pairs of shutter mechanisms, including electric motor means for adjustment thereof, mounted on said rotary support member, said shutter mechanisms defining a bi-directionally adjustable rectangular aperture which dictates the cross-sectional size and shape of the X-ray beam reaching the table top.

References Cited by the Examiner UNITED STATES PATENTS 1,976,179 10/1934 Mannl 250-405 2,552,858 5/1951 Mueller et al 250105 2,998,526 8/1961 Green et al 250105 FOREIGN PATENTS 53,010 4/1912 Austria. 706,378 3/1954 Great Britain.

RALPH G. NILSON, Primary Examiner.

W. F. LINDQUIST, Assistant Examiner. 

1. X-RAY APPARATUS COMPRISING SHUTTER MEANS DEFINING AN ELONGATED APERTURE WHICH DICTATES THE CROSS-SECTIONAL SHAPE OF AN X-RAY BEAM, AND ROTARY MOUNTING MEANS FOR SAID SHUTTER MEANS TO PERMIT SELECTIVE ROTARYWISE ORIENTATION OF SAID SHUTTER MEANS, WHEREIN SAID ROTARY MOUNTING MEANS IS IN THE FORM OF A CIRCULAR MEMBER AND SAID APPARATUS INCLUDES ROLLER SUPPORT MEANS ENGAGING THE OUTER RIM OF SAID MEMBER FOR ROTATABLE SUPPORT THEREOF, A MOTOR MECHANISM MOUNTED ON SAID MEMBER, A PULLEY MOUNTED ON SAID MECHANSIM AND ROTATED BY SAME, AND A TENSIONED FLEXIBLE CABLE MEANS ANCHORED AT BOTH ENDS AT SPACED POINTS ON SAID APPARATUS AND PASSING AROUND SAID PULLEY TO CAUSE SAID PULLEY TO TRAVEL ALONG SAID CABLE 